表面形貌对钯纳米环催化性能的影响
|
摘要
运用基于分子动力学方法的软件LAMMPS,在EAM势(嵌入原子势)函数下对一种钯纳米环结构贵金属催化剂材料进行了数值建模和计算,模拟了其工作过程中比表面积和不饱和配位活性位点数量受环境温度变化的影响,结合后处理软件OVITO对表面及截面原子排布情况进行了分析。结果表明:模型在温度变化过程中表面形貌演变出坑洞型及阶梯型原子排布,提供了更多配位不饱和的活性位点;比表面积、活性位点比例与升降温循环次数之间成反比关系,由此验证了其催化性能在工作过程中的降低趋势;且10次循环后损失低于5%,表明其具有很高的循环稳定性。
The influence of environmental temperature variation on specific surface area and amount of unsaturated-coordinated active sites in palladium nano-ring structure was simulated, for which some modeling and computation using embedded atom method and LAMMPS based on molecular dynamics method were carried out. Through analysis and visualization tool OVITO, the atomic arrangements on surface and cross section of the models were analyzed in detail. Results suggest that temperature fluctuation brings out pits and steps on surface as the morphology change, consequently introduce more unsaturated-coordinated active sites. Both specific surface area and proportion of active sites decreases while the numbers of temperature fluctuation loops(heating-cooling cycles) increase. As a result, catalyst performance degradation of the nano-ring is verified during the course of its operation. The degradation after 10 loops is less than 5%.
The influence of environmental temperature variation on specific surface area and amount of unsaturated-coordinated active sites in palladium nano-ring structure was simulated, for which some modeling and computation using embedded atom method and LAMMPS based on molecular dynamics method were carried out. Through analysis and visualization tool OVITO, the atomic arrangements on surface and cross section of the models were analyzed in detail. Results suggest that temperature fluctuation brings out pits and steps on surface as the morphology change, consequently introduce more unsaturated-coordinated active sites. Both specific surface area and proportion of active sites decreases while the numbers of temperature fluctuation loops(heating-cooling cycles) increase. As a result, catalyst performance degradation of the nano-ring is verified during the course of its operation. The degradation after 10 loops is less than 5%.
引文
[1] 高正中,戴洪兴.实用催化:催化[M].北京:化学工业出版社,2012:3.
[2] Greeley J,Stephens I E,Bondarenko A S,et al.Alloys of Platinum and Early Transition Metals as Oxygen Reduction Electrocatalysts [J].Nature Chemistry,2009,1(7):552～556.
[3] 周春晖,李小年.贵金属钯催化剂的研究现状和发展前景[J].化工生产与技术,2000,7(1):12.
[4] 野依良治.不对称催化:科学与机遇[J].化学通报,2002,(6):363～372.
[5] Xin B,Jing L,Ren Z,et al.Effects of Simultaneously Doped and Deposited Ag on the Photocatalytic Activity and Surface States of TiO2[J].Journal of Physical Chemistry B.,2005,109(7):2805～2809.
[6] Yun S Y,Wang K P,Lee N K,et al.Alkane C-H Insertion by Aryne Intermediates with a Silver Catalyst[J].Journal of the American Chemical Society,2013,135(12):4668～4671.
[7] Wang J,Gu H.Novel Metal Nanomaterials and Their Catalytic Applications[J].Molecules,2015,20(9):17070～17092.
[8] Xie S,Liu X Y,Xia Y.Shape-Controlled Syntheses of Rhodium Nanocrystals for the Enhancement of Their Catalytic Properties[J].Nano Research,2015,8(1):82～96.
[9] Shibata J,Hashimoto M,Shimizu K,et al.Factors Controlling Activity and Selectivity for SCR of NO by Hydrogen over Supported Platinum Catalysts[J].The Journal of Physicel Chemistry B.,2004,108(47):18327～18335.
[10] Akbayrak S,Tonbul Y,?zkar S.Nanoceria Supported Palladium(0) Nanoparticles:Superb Catalyst in Dehydrogenation of Formic Acid at Room Temperature[J].Applied Catalysis B Environmental,2017,206:384～392.
[11] 曹卉,芮执元,罗德春,等.温度对单晶γ-TiAl合金裂纹扩展的影响的分子动力学模拟[J].材料科学与工程学报,2016,34(4):607～613.
[12] 曹卉,芮执元,等.加载速率对单晶γ-TiAl裂纹扩展影响的分子动力学模拟[J].材料科学与工程学报,2016,34(2):321～325.
[13] 刘宁,胡振东.温度对NiAl合金纳米线应力诱发相变的影响[J].材料科学与工程学报,2016,34(4):545～549.
[14] 张博,薛红涛,等.Al纳米晶在Fe表面熔化行为的分子动力学模拟[J].材料科学与工程学报,2015,33(6):836～842.
[15] Wang Y G,Cheng L,Li F,et al.High Electrocatalytic Performance of Mn3O4/Mesoporous Carbon Composite for Oxygen Reduction in Alkaline Solutions[J].Chemistry of Materials,2007,19(8):2095～2101.
[16] Ichikawa M.“Ship-in-Bottle” Catalyst Technology[J].Platinum Metals Review,2000,44(1):3～14.
[17] 陈敏,马莹,宋萃,等.Ce-Pt-Pd/不锈钢丝网催化剂的制备与催化性能[J].催化学报,2009,30(7):649～653.
[18] Clair T P S,Goodman D W.Metal Nanoclusters Supported on Metal Oxide Thin Films:Bridging the Materials Gap[J].Topics in Catalysis,2000,13(1-2):5～19.
[19] Chen B,Dingerdissen U,Krauter J G E,et al.New Developments in Hydrogenation Catalysis Particularly in Synthesis of Fine and Intermediate Chemicals.[J].Applied Catalysis A General,2005,280(1):17～46.
[20] Hvolb K B,Janssens T V W,et al.Catalytic Activity of Au Nanoparticles[J].Nano Today,2007,2(4):14～18.
[21] 王红梅,李勇智,张静,等.纳米贵金属催化剂制备的研究进展[J].工业催化,2009,17(6):1～6.
[22] 李茸,刘祥萱,王煊军.纳米金属催化机理[J].化学推进剂与高分子材料,2007,5(6):9～13.
[23] Geim A K.Graphene:Status and Prospects[J].Science,2009,324(5934):1530～1534.
[24] Xiao H.Metal Dichalcogenide Nanosheets:Preparation,Properties and Applications[J].Chemical Society Reviews,2013,42(5):1934～1946.
[25] Li Y,Wang W,Xia K,et al.Ultrathin Two-Dimensional Pd-Based Nanorings as Catalysts for Hydrogenation with High Activity and Stability[J].Small,2015,11(36):4745～4752.
[26] Huang X,Tang S,Mu X,et al.Freestanding Palladium Nanosheets with Plasmonic and Catalytic Properties[J].Nature Nanotechnology,2010,6(1):28～32.
[27] 阎子峰.纳米催化技术[M].北京:化学工业出版社,2003:268～269.
[28] Wang Z,Wang H,Zhang Z,et al.Synthesis of Pd Nanoframes by Excavating Solid Nanocrystals for Enhanced Catalytic Properties[J].ACS Nano,2016,11(1):163.
[29] 宋学琴.配位化学[M].成都:西南交通大学出版社,2013,16.
[30] Liu P,Qin R,Fu G,et al.Surface Coordination Chemistry of Metal Nanomaterials[J].Journal of the American Chemical Society,2017,139(6):2122～2131.
[31] Plimpton S.Fast Parallel Algorithms for Short-Range Molecular Dynamics[J].Journal of Computational Physics,1995,117(1):1～19.
[32] Stukowski A.Visualization and Analysis of Atomistic Simulation Data with OVITO-the Open Visualization Tool[J].Modelling & Simulation in Materials Science & Engineering,2010,18(1):15012.
[33] Stukowski A.Computational Analysis Methods in Atomistic Modeling of Crystals[J].JOM,2014,66(3):399～407.
[34] Greeley J,N?rskov J K,Mavrikakis M.Electronic Structure and Catalysis on Metal Surfaces[J].Annual Review of Physical Chemistry,2002,53(1):319～348.
[2] Greeley J,Stephens I E,Bondarenko A S,et al.Alloys of Platinum and Early Transition Metals as Oxygen Reduction Electrocatalysts [J].Nature Chemistry,2009,1(7):552～556.
[3] 周春晖,李小年.贵金属钯催化剂的研究现状和发展前景[J].化工生产与技术,2000,7(1):12.
[4] 野依良治.不对称催化:科学与机遇[J].化学通报,2002,(6):363～372.
[5] Xin B,Jing L,Ren Z,et al.Effects of Simultaneously Doped and Deposited Ag on the Photocatalytic Activity and Surface States of TiO2[J].Journal of Physical Chemistry B.,2005,109(7):2805～2809.
[6] Yun S Y,Wang K P,Lee N K,et al.Alkane C-H Insertion by Aryne Intermediates with a Silver Catalyst[J].Journal of the American Chemical Society,2013,135(12):4668～4671.
[7] Wang J,Gu H.Novel Metal Nanomaterials and Their Catalytic Applications[J].Molecules,2015,20(9):17070～17092.
[8] Xie S,Liu X Y,Xia Y.Shape-Controlled Syntheses of Rhodium Nanocrystals for the Enhancement of Their Catalytic Properties[J].Nano Research,2015,8(1):82～96.
[9] Shibata J,Hashimoto M,Shimizu K,et al.Factors Controlling Activity and Selectivity for SCR of NO by Hydrogen over Supported Platinum Catalysts[J].The Journal of Physicel Chemistry B.,2004,108(47):18327～18335.
[10] Akbayrak S,Tonbul Y,?zkar S.Nanoceria Supported Palladium(0) Nanoparticles:Superb Catalyst in Dehydrogenation of Formic Acid at Room Temperature[J].Applied Catalysis B Environmental,2017,206:384～392.
[11] 曹卉,芮执元,罗德春,等.温度对单晶γ-TiAl合金裂纹扩展的影响的分子动力学模拟[J].材料科学与工程学报,2016,34(4):607～613.
[12] 曹卉,芮执元,等.加载速率对单晶γ-TiAl裂纹扩展影响的分子动力学模拟[J].材料科学与工程学报,2016,34(2):321～325.
[13] 刘宁,胡振东.温度对NiAl合金纳米线应力诱发相变的影响[J].材料科学与工程学报,2016,34(4):545～549.
[14] 张博,薛红涛,等.Al纳米晶在Fe表面熔化行为的分子动力学模拟[J].材料科学与工程学报,2015,33(6):836～842.
[15] Wang Y G,Cheng L,Li F,et al.High Electrocatalytic Performance of Mn3O4/Mesoporous Carbon Composite for Oxygen Reduction in Alkaline Solutions[J].Chemistry of Materials,2007,19(8):2095～2101.
[16] Ichikawa M.“Ship-in-Bottle” Catalyst Technology[J].Platinum Metals Review,2000,44(1):3～14.
[17] 陈敏,马莹,宋萃,等.Ce-Pt-Pd/不锈钢丝网催化剂的制备与催化性能[J].催化学报,2009,30(7):649～653.
[18] Clair T P S,Goodman D W.Metal Nanoclusters Supported on Metal Oxide Thin Films:Bridging the Materials Gap[J].Topics in Catalysis,2000,13(1-2):5～19.
[19] Chen B,Dingerdissen U,Krauter J G E,et al.New Developments in Hydrogenation Catalysis Particularly in Synthesis of Fine and Intermediate Chemicals.[J].Applied Catalysis A General,2005,280(1):17～46.
[20] Hvolb K B,Janssens T V W,et al.Catalytic Activity of Au Nanoparticles[J].Nano Today,2007,2(4):14～18.
[21] 王红梅,李勇智,张静,等.纳米贵金属催化剂制备的研究进展[J].工业催化,2009,17(6):1～6.
[22] 李茸,刘祥萱,王煊军.纳米金属催化机理[J].化学推进剂与高分子材料,2007,5(6):9～13.
[23] Geim A K.Graphene:Status and Prospects[J].Science,2009,324(5934):1530～1534.
[24] Xiao H.Metal Dichalcogenide Nanosheets:Preparation,Properties and Applications[J].Chemical Society Reviews,2013,42(5):1934～1946.
[25] Li Y,Wang W,Xia K,et al.Ultrathin Two-Dimensional Pd-Based Nanorings as Catalysts for Hydrogenation with High Activity and Stability[J].Small,2015,11(36):4745～4752.
[26] Huang X,Tang S,Mu X,et al.Freestanding Palladium Nanosheets with Plasmonic and Catalytic Properties[J].Nature Nanotechnology,2010,6(1):28～32.
[27] 阎子峰.纳米催化技术[M].北京:化学工业出版社,2003:268～269.
[28] Wang Z,Wang H,Zhang Z,et al.Synthesis of Pd Nanoframes by Excavating Solid Nanocrystals for Enhanced Catalytic Properties[J].ACS Nano,2016,11(1):163.
[29] 宋学琴.配位化学[M].成都:西南交通大学出版社,2013,16.
[30] Liu P,Qin R,Fu G,et al.Surface Coordination Chemistry of Metal Nanomaterials[J].Journal of the American Chemical Society,2017,139(6):2122～2131.
[31] Plimpton S.Fast Parallel Algorithms for Short-Range Molecular Dynamics[J].Journal of Computational Physics,1995,117(1):1～19.
[32] Stukowski A.Visualization and Analysis of Atomistic Simulation Data with OVITO-the Open Visualization Tool[J].Modelling & Simulation in Materials Science & Engineering,2010,18(1):15012.
[33] Stukowski A.Computational Analysis Methods in Atomistic Modeling of Crystals[J].JOM,2014,66(3):399～407.
[34] Greeley J,N?rskov J K,Mavrikakis M.Electronic Structure and Catalysis on Metal Surfaces[J].Annual Review of Physical Chemistry,2002,53(1):319～348.